| 摘要 |
PURPOSE:To heighten a switching speed of I<2>L, by connecting a constant current source to the base of a transistor and connecting a current source whose feed current increases at the time of turn-on of the transistor and decreases at the time of its turn-off in accordance with an input signal to the base. CONSTITUTION:A PNP transistor 4 is connected as a constant current source to the base of an emitter-grounded NPN transistor which acts as a switching transistor. A basic inverter of I<2>L is thus constructed. Another PNP transistor 15 is connected as a second constant current source. The base of the transistor 15 is connected to that of the inverter transistor 14 in the preceding stage. As a result, the capacitance between the base and emitter of the switching transistor 5 can be charged by both the output currents of the transistors 4, 14 which serve as the first and the second constant current sources when the switching transistor 5 is turned on. Said procedure results in shortening the time of the charging and in heightening the switching speed. |
